My harness is homemade, except for the Y harness. It's the one BRP includes in the hitch kit. I don't see how the Y harness and the pigtail on the module are long enough to get the module down by the saddlebag. According to the hitch installations instructions,
http://instructions.brp.com/content...ler Hitch Spyder RT&rel_part_number=219400854, the harness from the module to the trailer connector is routed under that panel as your photo shows but it goes up the area just under the seat.
Keep hunting Pete, you'll find it!
Just did some more looking. It looks like they've changed instructions. According to this one the module is below the seat but just behind the gas tank, not up just under the access panel.
http://instructions.brp.com/content... - Hitch (RT) 65492&rel_part_number=219400432.
You can find installation instructions at
http://instructions.brp.com/content/instruction-sheet/en_CA/e-instruction.html#tab=1. Just put hitch kit into the search box to get these.